// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_MIDI_USB_MIDI_DEVICE_H_
#define MEDIA_MIDI_USB_MIDI_DEVICE_H_

#include <stddef.h>
#include <stdint.h>

#include <memory>
#include <vector>

#include "base/callback.h"
#include "base/memory/scoped_vector.h"
#include "base/time/time.h"
#include "media/midi/usb_midi_export.h"

namespace midi {

class UsbMidiDevice;

// Delegate class for UsbMidiDevice.
// Each method is called when an corresponding event arrives at the device.
class USB_MIDI_EXPORT UsbMidiDeviceDelegate {
public:
    virtual ~UsbMidiDeviceDelegate() { }

    // Called when USB-MIDI data arrives at |device|.
    virtual void ReceiveUsbMidiData(UsbMidiDevice* device,
        int endpoint_number,
        const uint8_t* data,
        size_t size,
        base::TimeTicks time)
        = 0;

    // Called when a USB-MIDI device is attached.
    virtual void OnDeviceAttached(std::unique_ptr<UsbMidiDevice> device) = 0;
    // Called when a USB-MIDI device is detached.
    virtual void OnDeviceDetached(size_t index) = 0;
};

// UsbMidiDevice represents a USB-MIDI device.
// This is an interface class and each platform-dependent implementation class
// will be a derived class.
class USB_MIDI_EXPORT UsbMidiDevice {
public:
    typedef ScopedVector<UsbMidiDevice> Devices;

    // Factory class for USB-MIDI devices.
    // Each concrete implementation will find and create devices
    // in platform-dependent way.
    class Factory {
    public:
        typedef base::Callback<void(bool result, Devices* devices)> Callback;
        virtual ~Factory() { }

        // Enumerates devices.
        // Devices that have no USB-MIDI interfaces can be omitted.
        // When the operation succeeds, |callback| will be called with |true| and
        // devices.
        // Otherwise |callback| will be called with |false| and empty devices.
        // When this factory is destroyed during the operation, the operation
        // will be canceled silently (i.e. |callback| will not be called).
        // This function can be called at most once per instance.
        virtual void EnumerateDevices(UsbMidiDeviceDelegate* delegate,
            Callback callback)
            = 0;
    };

    virtual ~UsbMidiDevice() { }

    // Returns the descriptors of this device.
    virtual std::vector<uint8_t> GetDescriptors() = 0;

    // Return the name of the manufacturer.
    virtual std::string GetManufacturer() = 0;

    // Retur the name of the device.
    virtual std::string GetProductName() = 0;

    // Return the device version.
    virtual std::string GetDeviceVersion() = 0;

    // Sends |data| to the given USB endpoint of this device.
    virtual void Send(int endpoint_number, const std::vector<uint8_t>& data) = 0;
};

} // namespace midi

#endif // MEDIA_MIDI_USB_MIDI_DEVICE_H_
